Gas-detector.



No. 692,007. I Patented Ian. 28, I902. 0. F'REYMANN & c. TOLMAN.

GAS DETECTOR.

(Application filed Apr. 15, 1901.)

2 Sheets$heet I.

(No Model.)

WNW KM.

. Pa'tnted'lan. 28', 1902..

0'. FREYMANN 8|. c.- .TULMAN;

GAS DETECTOR.

(Application filed Apr. 15, 1901.) (No Model.) '2 Sheets-Sheet 2. I

wil'wzomz ammw f$ I m 2 5 mmawq o UNITE STATES PATENT OFFICE.

OSCAR FREYMANN AN-D CHARLES 'TOLMAN, or BROOKLYN, N W YORK,.

ASSIGNORS TO AMERICAN EQUIPMENT COMPANY, OF NEW YORK, N. Y.,

A CORPORATION OF NEW YORK.

GAS-DETECTOR.

SPECIFICATION forming partof Letters Patent No. 692,007, dated January 28, 1902.

Application filed April 15, 1 901- SerialNo. 55,897- (No model.) i

T on whom it may concern:

Be it known that we, OSCAR FREYMANN and CHARLES TOLMAN, of

lyn, county of Kings, city and State of New York, have invented certain new and useful Improvements in Gas-Detectors,;of which the following is a full, clear, and exact specification, reference being had to the accompanying drawings, wherein- Y Figure 1' is an elevation partly-sectional view of an apparatus gas-detector, showing one form of performing and using ourinvention. Fig. 2 is a similar view of the same apparatus, taken at right angles to Fig.1. Fig. 3 is a plan View thereof. I

Our invention relates to automatic alarm devices; and it consists of the hereinafterdescribed apparatus for detecting and sign aling the presence ofgas escaping in the place where the apparatus is located.

The apparatusshown and described herein is designed to be used in connection with an electrically-operated signaling device, its function in this combination being to effect the closing of the electric circuit; but the apparatus may also be used in connection with a mechanically-operated signaling device.

The operating parts of the apparatus shown in the drawings are arranged in and secured to a frame consisting of bracket 1 and plate 2, joined to insulating-plate 7 by screws 8 and 9, respectively, plate 3, bolts 4, joining plates 2 and 3 together, and brackets 5, whereby the frame is secured by screws 10 to the metallic casing 6, inclosing the apparatus. Gas

ing 6 is provided with aperture 37 and perforations 38 in thebottom .part thereof and with apertures 40 farther above to permit gas to freely pass through the apparatus.

40 casing is made integral with or affixed to a socket 42, whereby the apparatus can be atfixed to the wall or ceiling of a room.

The operating mechanism of the apparatus is arranged as follows: The stationary con tactpiece 29, connected by wire 31 to a battery or other generator of electric current, is set on top of bracket 1 and secured thereto by screw 30, and the movable contact-piece 27 is mounted upon the oscillating lever'25, which is pivoted the borough of Br0ok- The on pin 26, set in plates 2 and 3. This mov- 5o able contact-piece 27 is connected to the same battery or electric-current generator through lever 25, pin 26, plates2and 3, brackets 5, casing 6, and wire 28. In the" same electric current is included an electric hell or other signaling device, and also an annunciator, indicating the location of the appa ratus' by number or otherwise, may be in-' cluded therein. Lever 25 is provided with a recess 2i, wherein oscillating on pin 20, engages. Spring 32, secured on a pin set in plate 2, acts upon the shorter arm of lever 19, pressing it upwardly, and thereby its longer-arm engaging in recess 24 of lever 25, as hereinbefore explained, draws the movable contact-piece 27 downwardl y, pressing it in contact with the stationary contact-piece 29, whereby the electric circuit from the battery and through the signaling device and through the apparatus and back to'the battery is closed. I

The signaling device and the annunciator are set in action when the electric circuit is closed, and therefore the apparatus must norwith the contact-pieces separated from each other by adevice whose capacity for holding the contact-pieces apart will be destroyed by the action ofgas when entering the apparatus.

In the construction of our apparatus we utilize the substance known as platinum sponge, which, as it is well. known, becomes rapidly heated when exposed to the action of illuminating-gas. For the purposes of our apparatus it is best to prepare a bath of six parts of platinum chlorid and of twelve parts of aluminium chlorid, wherein a porous substancesuch as, for instance, rare clay, sepiolite, or the like-suitably shaped is immersed fora period of from two to three hours, 0 then dried, and afterward Washed in abath of hydrochloric or of sulfuric acid. This washing must be repeated until all impurities are removed, and then all traces of the acids washed out in a bath of water and 5 finally in a bath of ether. In place of rare clays or sepiolite coke may also be used; but. rare clays are best suited for the purpose.

the longer arm of lever 19, 6o

mally be held in inactive position to wit, 75

The porous substance is preferably made up in bars or plates, and such bars or plates prepared as hereinbefore described are then placed in close proximity to the device,whereby the contact-pieces are held separated and which must be such that heat acting upon it will cause it to relax or release its hold upon the contact-pieces or the mechanism pressing them one upon the other. When illuminating-gas enters the apparatus, it causes these bars or platesto glow, the heat emanating therefrom produces the desired efiect upon the device holding the contact-pieces separated, and the apparatus is thereby set in action.

In the construction shown in the drawin gs the device for holding the contact-pieces normally separated and for releasing, them by the action of gas is arranged as follows: The downwardly-pointing arm of bracket 1 is extended and formed into a shank 11, and a grooved roll 13 is mounted to loosely revolve on pin 14, set in tines 12 of its bifurcated end. On the end of the horizontal arm of bracket 1 a sleeve 15 is secured, wherein the shank of hook 16 is inserted and held by nut 17. The shank of hook 16 is bent to one side, as shown in Fig. 2, to bring the hook proper (designated 18 in the drawings) in line with the groove of roll 13. To this hook the connecting device 21, either combustible or expansible by heatas, for instance, a combustible thread or a metallic wire (preferably thin platinum wire)is secured. This connecting device is drawn over roll. 13, and its other end is secured to the short arm of lever 19 directly or through the medium of an intermediate hook 22, as shown in Fig. 1 of the drawings. Theconnecting deviceis stretched by screwing nut 17 on the end of shank 16, while the short end of lever 19 is pressed downward against the action of spring 32 to separate the movable from the stationary contact-piece. The bars, strips, or plates 33 of the porous substance treated as described above are supported on brackets 34, afiixed to shank 11, and are held in such position as to be almostin contact with the connecting device 21. When gas enters the apparatus, the connecting device 21, holding the contact-pieces separated, is heated, and if a metallic wire is used for that purpose is elongated. Lever 19 is thus released and yields to the action of spring 32 and the contact-pieces are brought together, the circuit closed, and the signaling apparatus set in action.

In place of a metallic wire a combustible thread may be used as the connecting device 21, with the same ultimate effect, except that instead of being elongated the combustible thread is destroyed by the glowing heat, and therefore must after every action of the apparatus be replaced, whereas if metallic wire is used the wire need not be replaced after every action of the apparatus, but merely readjusted, which is done by screwing nut 17 in the manner explained above.

The sensitiveness of the apparatus is adjusted by setting the movable contact-piece 27 farther away from or nearer to the stationary contact-piece 29. The greater the distance between the two the longer it will take to set the apparatus in action, and the nearer the contact-piece 27 is set to contactpiece 29 the sooner the alarm will be sounded.

Our improved apparatus for detecting gas escaping in a room may also be made so as to serve at the same time for detecting smoke in the manner described in our application for Letters Patent, filed April 1, 1901, Serial No. 53,803. For this purpose we use a thread of silk, a horsehair, or other similarly-composed fiber, which before using it we boil (in a closed vessel) in a six to ten per cent. solution of commercial soda for about twenty minutes and then dry it very moderately stretched in a tube from which the air is exhausted. The diameter of the fiber should not be less than that of the coarse horsehair. It is better to twist or braid two or three of such fibers into a string or cord, the capacity of such string or cord to be contracted by the treatment and elongated again when exposed to smoke being greater.

The solution of soda must not be stronger than ten per cent, and nothing but pure commercial soda must be used in preparing it. 'A'strong solution might impair the tensile strength of the fiber, which of course mustbe sufficient for the purpose of this appara tus, or might even dissolve it.

The thread, hair, or string is contracted by the treatment, but retains its tensile strength and acquires the quality to elongate when exposed to smoke.

We are unable to precisely explain what transformation is produced in the fiber by treating it as hereinbefore explained or what particular component of smoke produces its elongation. We believe that the vapors of volatile oils produced by combustion or some of the gases contained in the smoke produce the change in the composition of the fiber. We made numerous tests with fibers treated as above described and found that smoke invariably produced the elongation of the fiber thus treated, though some smoke-as, for instance, smoke produced by burning wood acts more rapidly than others.

Our gas-detecting apparatus thus amplified by the employment of such smoke-sensitive thread or fiber for the connecting device 21 signals the presence of smoke as well as of gas in the room or compartment wherein such apparatus is located, the smoke producing the closing of the electric circuit by elongating the sensitive thread, whereas when gas passes through the apparatus the sensitized fiber is disintegrated by the heat emanating from the glowing bars or plates 33. In both cases lever 19 is released and spring 32 presses the contact-pieces together, whereby the electric circuit is closed and the signaling or announcing device set in action.

We are aware that the principle of our invention may be embodied in still other forms of mechanical arrangement of theparts of such apparatus, and more particularly the combination of our gas'detecting apparatus withthe smoke-detecting apparatus described in our aforementioned application for patent may be accomplished in various otherways besides those we have shown; but we consider the apparatus illustrated in the drawings as the best form of the embodiment of our invention and the use of the sensitized fiber as the connecting device 21 as the best form of combination. whereby one apparatus can be made to serve for'both purposes simultaneously. i

We claim as. our i-nventi'on 1. The combination with an automatic circuit-closing device of a connecting device,

sensitive to the action'of heat, for holding the contact-pieces apart, and of a piece or pieces '7 of porous substance, affixed in proximity to the connecting device; said porous substance being treated with chemical composition as herein described and thereby rendered productive of heat when exposedto the action of gas. v v

2. The combination with the movable contact-piece of an automatic circuit-closing device of a connecting device, sensitive to the action of heat; said connecting device being attached to the movable contact-piece and holding it away from the other contact-piece,

and of a piece or pieces of porous substance, affixed in proximity to the connecting device; said porous substance being treated with chemical composition as herein described and thereby rendered productive of heat when exposed to the action of gas.

3. The combination with an automatic circuit-closing device, comprising a stationary and a movable contact-piece, of a connecting device, sensitive to the action of heat, attached to the movable contact-piece and holding it away from the other, and of a piece or pieces of porous substance, affixed in proximity to the connecting device; said" porous substance being treated with chemical composition as herein described and thereby rendered productive of heat when exposed to the action of gas.

i. The combination with mechanism, actuating a signaling device and a spring-actuated lever for starting or releasing the mechanism, of a connecting device, sensitive to the action of heat, attached to the lever and holdingit against the action of the spring, and of a piece or pieces of porous substance, affixed in proximity to the connecting device; said porous substance being treated with chemical composition as herein describedand thereby rendered productive of heat when exposed to the action of gas.

5. A gas-detecting device comprising an electric battery, an electrical signaling device, a frame, a stationary and a movable'contact-piece, mounted in the frame, electrical imity to the connecting device conduits connectingthe battery, the signaling device and the contact-pieces, mechanism acting upon the movable contact-piece, a connecting device, sensitive to the action of heat, attached to the movable contact-piece and holding it away from the stationary contactpiece, and a piece or pieces of porous substance, affixed in proximity to the connecting device; said porous substance being treated with chemical composition as herein described and thereby rendered productive of heat when exposed to the action of gas.

6. A gas-detecting device comprising an electric battery, an electrical signaling device, a frame, a stationary and a movable contact-piece, mounted in the frame, electrical conduits connectingthe battery, the signalin g device and the contact-pieces, mechanism acting upon the movable contac t-piece, a connecting device,sensitive to the action of heat,

connected to the movable contact-piece and holding itaway from the stationary contactpiec'e, and a piece or pieces of porous substance, affixed in proximityto the connecting device; said porous substance being treated with chemical composition as herein described and thereby rendered productive of heat when exposed to the action of gas.

7. The combination with an automatic circuit-closing device of a combustible connecting device for holding the contact-pieces apart, and of a piece or pieces of porous substance, aftixed in proximity to the connecting device; said porous substance being treated with chemical composition as herein described and thereby rendered productive of heat when exposed to the action of gas.

8. The combination with mechanism actuating a signaling device and a spring-actuated leverfor starting'or releasing the mechanism, of a combustible connecting device attached to the lever and holding it against the action of the spring, and of a piece or pieces of porous substance, affixed in proximity to the connecting device; said porous substance being treated with chemical composition as herein described and thereby rendered productive of heat when exposed to the action of gas.

9. 'A gas-detecting device, comprising an electric battery, an electrical signaling device, a frame, a stationary and a movable contact-piece, mounted in the frame, electrical conduits connecting the battery, the signalin g deviceand the contact-pieces, mechanism acting upon the movable contact-piece, a combustible connecting device attached to the movable contact-piece and holding it away from the stationary contact-piece, anda piece or pieces of porous substance, affixed in proxsaid porous substance being treated with chemical composition as herein described and thereby rendered productive of heat when action of gas. 1

10. The combination with an automatic circuit-closing device of a combustible connect in g device for holding the contact-pieces apart,

exposed to the ICO said connecting device being treated as herein described, whereby it is rendered sensitive to the actionof smoke, the smoke causing it to elongate, and of a piece or pieces of a porous substance, affixed in proximity to the connecting device; said porous substance being treated with chemical composition as herein described and thereby rendered productive of heat when exposed to the action of gas.

11. A combined smoke and gas detecting device comprising an electric battery, an electric signaling device, a frame, a stationary and a movable contact-piece, mounted in the frame, electric conduits connecting the battery, the signaling device and the contactpieces, mechanism acting upon the movable contact-piece and forcing it in contact with the stationary contact-piece; a combustible con- 

